High-frequency oscillation generator



Nov. 12, 1929. A. H. TAYLOR I HIGH FREQUENCY OSCILLATION GENERATOR FiledDec. 22. 1928 M at an Patented Nov. 12, 1929 UNITED s'rzrras PATENTorrlcr;

ALBERT H. TAYLOR, OF WASHINGTON,DISTBIG T OF COLUMBIA, ASSIGNOR 'IOWIRED RADIO, ING, OF'NEW YORK, N. Y., A CORPORATION OF DELAWAREnrerr-rnnounncv 'oscrrna'rroiv ennnna'ron Application flled necember 22,1928; Serial No. 327,937.

quency oscillation generators wherein the generator is to produceoscillations of any one of a plurality of frequencies.

An objectof this invention isrto provide means in a high frequencyoscillation generator employing piezo electric crystal frequencycontrol, whereby the frequency of the oscillations generated may bereadily changed.

Another object of this invention is to pro- -vide means in a piezoelectric crystal frequency controlled high frequency oscillationgenerator whereby the frequency of the osc1llations generated may bereadily changed from one predetermined constant value to another withoutdestroying the effect of piezo electric crystal frequency control. Afurther object of this inventlon is to provide means in a piezo electriccrystal.

frequency controlled oscillation generator whereby any one of aplurality of piezo electric crystals maybe readily used to control thefrequency of the oscillations generated.

An ancillary object of this invention is to connect a plurality of piezoelectric crystals into a circuit arrangement with an electron tubeoscillation generator having a plurality of grid electrodes whereby anyone' of the piezo electric crystals may be readily used to control thefrequency of the oscillations generated.

A further object ofthis invention is to provide a piezo electricfrequency controlled high frequency -oscillation generator circuit oflarge output.

filament and anode of the electron tube. This Other features of thisinvention will be apselective circuit is tuned to .the frequency of anyone of the iezo electric elements whereby the electron tu e oscillationgenerator generates high frequency oscillations corresponding to thefrequency of the piezo electric element selected. r In the drawing, thefigure illustrates a circuit arrangement embodying this invention.

Referring to the drawing in detail, the reference character 1 designatesa thermionic vacuum tube in which are incorporated the anode 2, gridelectrodes 3 and 4 and filament or cathode electrode 5. The thermionicvacuum tube may be of the ordinary two grid type or it may be of theshield grid type; in the latter case, the shield grid electrodecorresponds to electrode 3 of the figure. 'Reference character 6designates the source of supply for the cathode 5. A choke coil 7 isconnected to the cntrol electrode 4 and biasing' source of potential 7The control electrode 3 is connected to one terminal of a choke coil 8.The other terminal of-the coil 8 is connected to a voltage dividerl0'which is connected across the source of anode potential 11. Thesources of potential? and 11 are connected to the filament 5. A capacity9 is connected across the source of supply 11 and furnishes a highfrequency circuit across the source. An inductance 12 havinga capacity13 associated therewith'is connected to the anode electrode 2 of thethermionic vacuum tube. Piezo electric elements Q, Q, and Q areconnected to the grid electrodes of the thermionic vacuum tube 1.Element Q, is connected between the electrode 3 and the cathode 5;element Q is connected between theelectrode 4 and the cathode; andelement Q qis connected to the electrodes 3 and 4. If the three piezoelectric elements Q Q and Q each have different fundamental frequencies,oscillations of three dilferent frequencies may be generated by the 0oscillation generator without substituting diiferent piezo electricelements for those in circuit.

Any one of the elements may be used to control the frequency ofoscillation by adjusting the resonant frequency of the circuit l213 tocorrespond, or approximately cor- ,7 lations generated.

the element. For example, when piezo electric element Q, is to be usedas a frequency control the resonant frequency of the circuit 12 13 isadjusted to equal or approximately equal that of Q In a similar mannerany one of the elements Q and Q may be employed to control the frequencyof the oscil- The oscillation generator embodied in this invention maybe employed in an arrangement where it is desired to obtain frequency.controlled oscillations of large amplitude without resorting to the useof power amplifiers. .lVhen the piezo electric elements Q,

Q, and Q are so chosen that they all possess an identical fundamentalfrequency, oscilla-- tions of large amplitude. are generated since thepiezo electric elements all function simultaneously. Greater poweroutput may then be obtained from a piezo electric crystal controlledoscillation generator. Obviously some of the amplifiers usuallynecessary to increase the amplitude of the oscillations before they, areimpressed upon the large capacity power amplifier are eliminated inarrangements employing the oscillation generator of this invention.Greater operating efficiency is thus obtained.

While I have described my invention in one of its preferred embodiments,I desire that it be understood that modifications of this invention maybe made and that no limitations upon the invention are intended otherthan are imposed by the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is as follows 1. A high frequency oscillation generatorcomprising in combination, a thermionic discharge device having acathode electrode, a plurality of control electrodes and an anodeelectrode, input and output circuits connected with said electrodes andseparate mechanically vibratile frequency control elements connected toeach of 'said control electrodes and to said cathode electrode.

2. A high frequency oscillation generator an inductance and anelectrostatic capacity connected to said anode electrode and saidcathode electrode, a plurality of piezo electrio crystals, individualpiezo electric crystals bein connected between said grid electrodes andetween each of said grid electrodes and said cathode electrode.

4. A high frequency oscillation generator comprising in combmation, athermionic electron discharge device having a cathode electrode, aplurality of control electrodes and an anode electrode, input and outputcircuits connected to said electrodes and meohanically vibratileelements associated with said input circuits, individual elements beingindependentlyconnected between said control electrodes and between saidcontrol electrodes and said cathode.

5. In a high frequency oscillation generator the combination of athermionic electron discharge device having acathode electrode, aplurality of grid electrodes and an anode electrode, an output circuitincluding an inductance and an electrostatic capacity connected to said"anode electrode and said cathode electrode, a plurality of piezoelectric crystals each having a different fundamental frequency,individual piezo electric crystals being connected between said gridelectrodes and between each of said grid electrodes and said cathodeelectrode.

ALBERT H. TAYLOR.

